VOUT

RESET

ALERT

IN+

IN-

VS+

GND

CMPIN

CMPREF

10 k:

+

-

0 V to 26 V

+

-

G = 20, 50,

100, 200

ADC

GPIO

GPIO

R1

R2

Microcontroller

5 V

2.7 V to 5.5 V

Load

INA381

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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. ADVANCE INFORMATION for pre-production products; subject to

change without notice.

INA381

SBOS848 – DECEMBER 2017

INA381 26-V, Low-Cost, Zero-Drift, Voltage-Output,

Current-Shunt Monitor With Integrated Comparator

1

1 Features

1

•

Common-Mode Input Range: –0.2 V to 26 V

•

High Accuracy Amplifier:

–

(Maximum)

–

–

Offset Voltage Drift: 1 µV/°C (Maximum)

–

Gain Error: 1% (Maximum)

–

Gain Error Drift: 20 ppm/°C (Maximum)

•

Available Amplifier Gains:

–

INA381A1: 20 V/V

–

INA381A2: 50 V/V

–

INA381A3: 100 V/V

–

INA381A4: 200 V/V

•

Comparator Specifications:

–

Hysteresis: 50 mV

–

Response Time: 500 ns

–

Alert Threshold Set Through External

Reference Voltage

•

Open-Drain Comparator Output With Latching

Mode

•

Package: WSON-8 (2 mm × 2 mm)

2 Applications

•

Overcurrent Protection

•

Power-Supply Protection

•

Low-Side Phase Motor Control

•

Computers and Servers

•

Telecom Equipment

3 Description

The INA381 device includes both a 26-V common-

mode, current-sensing amplifier and a high-speed

comparator

configured

to

detect

overcurrent

conditions through measuring the voltage developed

across a current-shunt resistor and comparing that

voltage to a defined threshold limit set by the

comparator reference pin. The current-shunt monitor

can measure differential voltage signals on common-

mode voltages that can vary from –0.2 V up to 26 V,

independent of the supply voltage.

The open-drain alert output can be configured to

operate in either a transparent mode where the

output status follows the input state or in a latched

mode where the alert output is cleared when the latch

is reset. The standalone comparator alert response

time is under 5 µs, allowing for quick detection of

overcurrent events. The total system overcurrent

protection provided by the INA381 is under 10 µs.

This device operates from a single 2.7-V to 5.5-V

supply, drawing a maximum supply current of 400 µA.

The device is specified over the extended operating

temperature

range

(–40°C

to

+125°C),

and

is

available in an 8-pin WSON package.

Device Information(1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

INA381

WSON (8)

2.00 mm × 2.00 mm

(1) For all available packages, see the orderable addendum at

the end of the data sheet.

Typical Application